Art of making metal castings.



l T. D. WEST.

ART 0F MAKING METAL CASTINGS.

APPLICATION FILED JAN. 22, 1912.

1,031,305. Patented July 2,1912.

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T. D. WEST.

ART or MAKING METAL CASTINGS.

APPLICATION FILED JAN. 22, 1912. 1,031,305, Patented July 2, 1912.

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Am: or unirme METAL CASTINGS.

Specification of Letters Patent.

Patented July 2, 191.2.

Applicationmed January 22, 1912. semi No. evans.

` To all wwm 'it may concern:

Be it known that I, THOMAS D. WEST, a citizen of the United States of America, residing at Cleveland, in the count-y of Cuyahoga and State of Ohio, have invented certain new and useful Improvements in the Art of Making Metal Castings; and I hereby declare the followin and exact description o the invention, such as will enable others skilled in the art to which it pertains to make and use the Same.

This invention relates to improvements in the art of making metal castings, and more especially to an improved process of casting circular objects, such, for instance, as carwheels and rolls.

The primary object of this invention is to treat a body of hot metal in a mold, upon the formation of a crust on said body of metal, with a heat-absorbing medium, such, for instance, as air, drawn through the mold by suction between said crust and thecrustfacing portion of the mold and thereby carry off heat from the metal While the crusted body of metal or'casting is within the mold and beneficially affect or influence the casting in any one or more of various ways, such, for instance, as Increasing the de th or hardness of chilling beyond the chilling or hardening capacity of a metal chiller or chill, or hardening the surface of .any casting while the castingis within the 'n1old, or effecting molecular changes in said casting to better qualify it to withstand any ordinary or special service to which 1t may be subjected, or preventing shrink-holes or contraction-cracks in the casting or prevent- 'ing warping or distortion of the casting, or l'rendering the'casting stronger o r more dura- `ble. orr producing what I term an inside chilling,-`-that is, a chilling of the casting at a pointI spaced inwardly from the surface or exterior of the casting.

Another Objectis to inexpensively create or establish a steady passage in ample volume of said air or heatabsorbin medium along or next exteriorly ofand 1n contact with. the cooling and contracting casting and through the mold while said casting is withinthe mold and efficiently and expeditiously effect, the hereinbefore indicated beneficial influence upon the strength, durability, depth of chill or other quality of the casting.

Another object is to carry out my invention more especially in the casting of a cirto be a full, clear,-

cular object, such, -for instance, as a clrwheel, by, first, pouring a mold having a circular chamber for'rcceiving molten metal and, upon the formation of aV peripheral crust on the body of hot metal supplied to said chamber and the creation of an annular space next exteriorly df and surrounding said crust whilesaid body of metal or casting is wit-hin the mold, creating suction within said space uniformly all around the 'casting being treated and by said suction drawing air or other heat-absorbing medium through and endwis'e of said space uniformly all around the casting and thereby carryin off heat from or treating the casting uni ormly all around the casting.

Another object is to carry out my invention, in casting a metal car-wheel having a flange at one end of the tread-forming portion of the wheel, in such a manner that the 75 the wheel shall be acted upon by my ims.

proved process to increase the depth of chill or hardness at said tread and throat without having said flange, and more especially the rounded periphery of the flange, correspondingly treated to any appreciable extent, so as to produce a cast-metal car-wheel which possesses great durability at its tread and .throat without having the peripheral portion of the flange` treated in a way that would render the flange unduly britt-le and thereby susceptible of being readily broken off or chipped.

Another object is to cool the core of a mold adapted for use in casting an annular object, such, for instance, as a car-wheel, and to materially cool the casting at and around the core before removal of the casting from the mold, and more especially to effect said cooling of said core and t-he adjacent core-surrounding portion of the cooling and contracting casting by sucking or drawing air or heat-absorbing medium through said core simultaneously with the sucking or drawing of air or heat-absorbing medium through the mold at the peripheral surface of the casting and thereby prevent the creation of undue strains in the outer portion of the casting.

With these objects in view, this invention consists in the steps or features hereinafter described and pointed out in .the claims.

' A mold suitable for use i'n carrying out my invention in the manufacture-of a carwheel-bium at its tread and throat is illustrated in whichy Figure 1 is a central vertical section of the said moldready for pouring. Fig. 2 is ,a central vertical section of the mold, showing a car-wheel H cast within the mold. Fig. 3 is an enlarged view of a portion of Fig. 1. Fig. 4 isan enlargedV view of a portion of Fig. 2. Fig. 5 is a vertical section on line 5 5, Fig. 3, looking outwardly.

The mold -illustrated consists in the main of an upper mold-part or cope, a lower moldpart or drag and a central mold-part which is shown formed in the main by a sectional chiller or chill.

Referring to the drawings, A indicates a the accompanying drawings, in

vertically arranged annular casing which,

forms a portion of the lower mold-part or drag and rests upon a horizontally arranged plate 10 forming the bottom of the drag and provided with a vertically downwardly projecting annular flange4 13 serving to` elevate said bottom above the floor or support upon' which the mold is to be mounted. The drag is rammed with sand or substantially nonchillin material, and the top or upper portion o the body of packed sand 14 of the drag has the contour required to form the bottom of the casting.

B indicates a vertically arranged suitably supported annular metal l casing which forms a portion of the upper mold-part or cope. The cope is rammed with sand, and theV body of packed sand 15 of the cope has its bottom or lower portion contoured as required to form the top' of the casting. The cope and the drag are spaced verticall to form a chamber C between them, w ich chamber is enlarged diametrically and annularly at its. lower end, as at 12.

'The central mold-part comprises an annular vertically arranged sectional chiller or chill consisting of two superimposed annular sections D and d instrumental in forming the surroundin wall of the chamber C. The chill-sections, Ig; and 'd are arranged vertically and in line endwise. The upper or main chill-section D is preferably of cast iron, whereas the lower chill-section d may be of steel.

Figs. 2 and 4 show a wheel-forming casting H in the mold, and, referring to said figures of the drawlngs, h indicates the annular flange formed on and externally of said casting at one end of the casting, which flange is shown formed at the lower end of the casting and has a rounded peripheral surface, and the throat 16 of the wheel formed by Said casting is formed at the junction of the inner side of said ilange with the tread 17 of the wheel. The flange of a car-wheel to be cast in the mold illustrated is obviously therefore formed next above the outer portion of the drag. The lower section required to form the bottom wall and lower portion of the surrounding wall of said enlargement of the -said chamber. 'The surrounding'wall of the chamber C is formed in the main by the internal annular surface 18 of the up er chill-section and the tread of the -cariieel to be cast in the mold is formed at said surface. The upper inner portion 19 of the lower chill-section is arranged below the lower end of-said surface 18 of the upper chill-section and has its linternal surface arranged flush with said surface 18 at the lower end of said surface 18 and contoured as required to render said portion of the lower chill-section instrumental in effecting the formation of the throat 16 of the wheel, and said portion 19 of the lower chill-section is arranged to form the inner portion of the top wall of the diametrical enlargement 12 of the chamber C. An annular body s of packed sand or substantially nonchilling material is applied to the lower chill-section in any approved manner and arranged to form the outer portion of .the enlargement 12 of the chamber C and forms the upper portion of the surrounding wall of said enlargement of said chamber and extends from-the sand-body 14 of the drag to the portion 19 of said chillsection. By having thediametrical enlargement 1.2 of the molten-metal-receiving chamsuccessfully avoided and the wheel is not only chilled at its tread but also chilled at its throat,

The lower chill-section is mounted on. the drag-casing A, and said drag-casing is provided at its top with a laterally and outwardly facing annular shoulder 21 which is overlapped by said chill-section so as to prevent displacement of the said chill-seetion horizontally independently of the drag. The lower chill-section is provided at the top and substantially vertically above the' shoulder 21 with a laterally and outwardly facing annular shoulder 22 which is voverlapped by lugs 23 formed on and projecting downwardly from the upper chill-section and spaced circumferentially of said shoulder 22. The shoulder 22 and the lugs 23 are instrument-al in centering the upper chill-section relative to the lower chillsection during the assemblagey of the component parts of the mold. The upper chill-section rests at its lugs 23 on thc lower chill-section. The upper chill-section is shown provided at the lower end of itsintei-nal surface 18 with a laterally inwardly and downwardly facing beveled annular shoulder 24 which is closely overlapped by the portion 19 of the lower chill-section, and an annular` space 25 is formed betweenv the bottom of the upper of the lower chill-section and arranged sub-- stantially concentrically relative to tbeclull and in communication between the lugs 23 with the external atmosphere, and the upper chill-section is free to expand laterally andoutwardly by heat independently of the lower chill-section. I

Any suitable number of bolts are employed in removably attaching the upper chill-sectionto the lower chill-section, and in Figs. 1 and 2 E indicates one of'said bolts. The bolt E .is shown extending i through a slot'- 26 which extends vertically through a lug 27 formed on the u-pper chillsection and through a lug 28 formed on the lower c hillsection. .Said bolt has its head Y rest-ing on thev top surface of the lug 27, and

a nut e is screwed onto the bolt at the bottom of the lug 28. The relative arrangement of the parts is such that in 'the normal condition ot the upper chill-section, before any lateral and outward expansion of said chill-section by heat, the bolt E, as shown in Fig. 1, is arranged next the outer end wall of the engaging slot 26 which is arranged radially of the chill and extends inwardly beyond said bolt toward the chamber C far enough to accommodate a lateral and outward expansion of the said chill-section by heat -independently of the lower chill-section.

The cope is mounted on the upper chillsection. Thefcope-casing B is provided at its bottom and in -proxlmity to the circum- Y erential surface of said casing with a downwardly projecting annular flange 30 which is arranged concentrically relative to the mold, and said cope-casing rests at said flange on the top of the upper chill-section. The outer side ofV the flange 30 is overlapped by the upper chill-section so as to acilit-ate centering of the cope relative to said chill-section during the assemblage of the component parts of the mold. The upper chill-section is provided at4 the upper end of its internal Surface 18 with a laterally inwardly and upwardly facing beveled annular shoulder 31, and the inner lower portion of the cope-casing terminates at the bottom in a downwardly and laterally inwardly pro1ecting flange 32 which closely A .overlaps the upper portion of the beveled surface 31 of the said chill-section. The flanges 30 and 32 of the cope-casing form oppositeside walls respectively of an annular Vrecess 33 formedin theunder side of said cope-casing and extending circumferentially but arranged externally of the chamber C and out of communication with` chill-section and the top said chamber in the normal condition of the upper chill-section.

Any suitable number of vertically arranged bolts are employed in removably at'- taching the cope-casing to the upper chill- Section, and G indicates one of said bolts. rlhe bolt (l extends vertically through a lug formed on the cope-casing and through a slot 36 which is formed in and extends vertically through a lug 37 formed on the upper chill-section. which slot is arranged radially of the chill. The bolt'G has its head resting on the top surface of the lug 35, andthe shank of the bolt extends a suitable distance below `the lug 37, and a nut g is screwed onto said bolt at the bottom of the last-mentioned lug, The relative arrangement of the parts is ysuch that in the normal condition of the upper chill-section, before any lateral and outward expansion of said chill-section by heat, the bolt Gr, as shown in Figs. l :uid 3, is arrangediiext the outer end wall of the engaging slot 36 which extends far enough inwardly beyond the said bolt toward the chamber C to accommodate the lateral and outward expansion of the said chill-section by heat independently of the lower chill-section.

The cope-casing is provided interiorly with an annular chamber b which is substatially concentric relative to the mold and arranged above and spaced from the recess 33 in the bottom of said casing, and vertically arranged holes 38 formed in said casing between saidv recess and said chamber and placing said recess in communication with said chamber are spaced circumferentially of the chamber C, and said recess 33 is of course wide enough to be in communication with'said holes not only in the normal and unheated condition of the upper chill-section, as shown in Figs. 1 and 3, but also during and uponpthe lateral and outward expansion 'of said chillsection by heat during the operation of the mold, as shown in Figs. 2 and 4L The recess 33 is therefore continuously in com munication with the chamber L, but is out of communication with the chamber C in the normal condition of the upper chillsection. A suction-pipe 40 for conducting air or other Huid from the chamber b is placed at its fluid-receiving endvin communication with said chamber and communicates at its delivering end with the inlet 41 (see Fig. 1) of a suitably operated rotary air-pump or suction-creating device l which has its outlet 42 Communicating with the external atmosphere.

The lower portion of the beveled shoulder 31 of the upper chill-section is covered by the sand-body 15 of the cope around the bore in said chill-section. and said sand-body is provided in and centrally of its under side with a cavity 43 forming the upper central portion of t-he chamber C, and the sand-body 14 of the drag is provided with a cavity 44 which forms the lower central portion of said chambcrk The sand-body l5 of the cope is provided in its under side and next the internal surface 18 of the upper chill-section with an annular recess Q0 which is arranged concentrically relative to said chill-section and forms an upward annular enlargement of the chamber C. The cope and the drag of the mold illustrated are shown rammed to lit them for casting a car-wheel which has a hub provided with a central bore extending therethrough, and consequently a baked hollow sand-core fis arranged vertically and cen` trally of the chamber C and shown extending through said chamber from the. bottom of the cavlty 44 to the top wall of t-he cavity 43. The top wall of the cavity 43 forms the bottom of a pouring basin 45 formed in any approved manner and having its bottom shown provided with a gate 4Glwhich establishes communication between said basin and the chamber C.

The casting formed in the mold obviously contracts horizontally or diametrically when it cools and thereby frees the chill, and obviously during the first cooling and contraction of a casting formed in the mold the upper chill-section expands laterally and outwardly by heat. The lowerchill-section, having the reater portion of its inner'portioirrcovere by the sand-body s carried by said chill-section and having its upper inner portion 19 comparatively thin, does not transmit enoughheat tothe much thicker body formed by the ccntraland outer portions of said chill-section to effect any material expansion of said, chill-section during the lateral and outward expansion of the upper chill-section. c

In carrying out my invention in the casting of a chilled car-wheel chillable molten iron or metal is used and the mold illus.- trated is oured. A peripheral chilled crust quickly orms on the body of hot chillable metal supplied to the chamber C and the normal cooling or contraction of the crusted and circumferentially chilled body of metal or casting takes place, and the upper chillsection expands laterally and outwardly by heat independently of the lower chill-section during said cooling or contraction of t-he casting. Said cooling or contraction of the casting a-nd'th'e lateral and outward expansion of the upper chill-section by heat during said lcooling and contraction of the casting not Vonly create an annular space next exteriorly ofand surrounding .the'casting, as shown in placing the space 25, which is formed-between vthe two chill-sections and communicates with the external atmosphere, into communication with the first-mentioned space all around th'e casting and in placing Figs. 2 and 4, but result in said first-mentioned space into communication at the top of the upper chill-section and all around the casting with the recess 33 in the bottom of the cope-casing B and consequently with the inlet of the pump or suction-creating device I. That is, the lateral 'and outward expansion of the upper chillsection independently of the lower chill-section results in the .spacin of the shoulder 24 on .the upper chill-section from the portion 19 of the lower chill-section, as shown in Figs. 2 and 4, so as to place the space 25 between the twoV chill-sections in communication with the chamber C all around the peripheral surface of the casting being treated in said chamber, and obviously air or heat-absorbing medium is supplied to the annular space formed next exteriorly of and around the peripheral surface 'of the casting during. the cooling or contract-ion` of the: .'85V

casting while the casting is-within the mold. The lateral and outward'expansion of the upper chill-section also results in the 4spacing of the shoulder 31 of said chill-section from the flange 32 of thevcope-casing,pas shown in Figs. 2 and 4, so as to place the annular space created around the casting 7during the cooling and contraction of-the castinginto communication all around the chamber C with the recess 33, and consequently with the inlet of the pump or suction-creating device I, and when said spacelias been placed in communication adjacent the throat of the car-wheel being cast with the external atmosphere and placed at its upper end in 'communication with' the inlet of the pump or suction-creating device the lat-ter is operated t-o draw air or heat-absorb-A o ing medium into and upwardly through said space created next exteriorly of and around the circumferential or peripheral surfaceiof the casting While the casting is within the mold. The heat-absorbing medium sucked or drawn through said space while the casting is within the mold andQ cooling or contracting within the moldabsorbsheat from the metal and isggdrawn to :thesexternal atmosphere from the upper "'fi'p.` Q-,said space through the recess v33, he "38611941117 ber ZJ and pump or suction"A c` tuig device I. The air or heiabsorbipngmedium sucked .or drawn through the annular ace created around the peri heral surface-1o ythe casting during thel coo ing, and contraction hasta.

of the casting enters said space .a

in proximity to thediambl'cal 'ehl gement 12 of the chamber Cjovfjthegfld quent-ly at the lower endbfthefi rm'- ing surface of the coolingand'contra'ctng casting and in proximity to the thrfoatlofthe.

pump or the suction-creating devicefl when saidspace has beenr placed in communication wheel being cast, and upon operatingthe Y iso mamon or heat-absorbing medium is continually su plied to said space from between said ch1llsection,that is, through the chill, so as to supply air or heat-absorbing medium in ample volume to said space and cause said air or heat-absorbing medium upon entering the said space to pass upwardly througlh the said space and carry 0H heat from t e cooling and contracting casting being treated in the mold and thereby beneficially aiect the casting in any one or more of several ways already hereinbefore described. would here remark that when a chlll is used in forming the surrounding Wall of the molten-metalreceiving chamber-of the mold, as in the mold illustrated, the crust formed on the body of hot metal or casting .1s of course chilled, but that the depth of chllling of the casting is materially increased by the treatment of the crusted body of hot metal or casting with air or other heat-absorbing medium hereinbefore described, and that in carrying out my invention in the casting of a car-wheel having a flange at one end of the tread-forming portion of the Wheel, as illustrated, the introduction of the air or otherheat-absorbing medium in proximity to the throat of the wheel being ca .st materially improves the durability o said throat Where durability is more especially needed.

The core f is provided centrally with a pipe K arranged substantmlly .verticallyand centrally of the core, whlch pipe 1s provided with lateral vent-holes 47 for permit-ting detrimental gases to escape from within the core into said pipe during the operation of the mold. The pipe K is provided at its upper end witlra suit-ably applled head 48 and at its lower end-communicates through an aperture 50 formed in the sand-body 14 of the 'drag adthrough a hole 51 formed Vin the plate 10 with the externalatmosphere.

The pipe K is placed in communicatmn at its upper end' by a pipeL, which extends through the sand-body 15 of the cope, with the chamber b in the cope-casing and consequently with the inlet of the pump or suction-creating device I. Obviously therefore during the operation 'of said pump' or suction-creating device to draw air or heatabsorbing medium through the mold at the peripheral surface of the cooling or contracting casting air or heat-absorbing me. dium is simultaneously drawn through the core f Without coming in direct contact with the casting. The sucking or drawing of air or heat-absorbing medium endwise through the core during the drawing of air or heatabsorbing medium at and transversely of the treadforming surface of the cooling and contracting casting not onlyrapidly coolsv the core and the adjacent core-surrounding portion of the casting but successfully prevents the creation of undue strains 1n the outer portion of the casting.

In carrying out my invention in the art of casting a met-al car-Wheel having a vflange at one end of the tread of the wheel as hereinbefore described, it will Vbe observed that `upon pouring the mold and liorming a chilled peripheral crust on and circumferentially of the body of hot metal supplied to the mold and creating a space next exteriorly of and around said chilled crust while the crusted body of hot metal or casting is within the mold 'it is not unimportant during the creation of said space to eiect, as hereinbefore described, the creation for said space of an entrance and an exit which extend all around said space adjacent opposite ends respectively of the tread-forming portion of the casting, so that during the operation of the pump or suction-creating device .I air or heat-absorbing medium is sucked or drawn at said entrance `into said space all around the casting and sucked or drawn at said exit out of said space from all around the casting, thereby insuring-the passage of a uniform and equal volume of air or heatabsorbing medilun through every portion of said space between said entrance and ysaid exit and consequently insuring uniformity in the action or influence by said air or heatabsorbing medium Ion the casting all around the casing. As shown in Figs. 3 and 4 the incline formed by the bevel of the shoulder 24 on the upper chill-section is preferably steeper than the incline formed by the bevel of the shoulder 31 on said chill-section. I would also remark that although I have shown the entrance to said space adjacent the throat-forming portion of the casting,- that is, at or in proximit to the inner side of the flange of the cast1ng,-the action or infiuence of said heat-absorbing medium on the casting will effectively reach said throatforming portion of the casting, but the creation of said entrance to said space at the inner side of or above the flange of the castingis not unimportant' to prevent any material action or influence by the heat-absorbing medium on the peripheral portion of the flange of the casting. l

What I claim isz# 1. An improvement in the art of making metal castings, said improvement consisting in pouring a mold in which a casting is to be formed, and then sucking or drawing a heat-absorbing medium to the casting and through the mold to 4carry ofi' heat from the casting while the casting is within the mold.

2. An improvement in the art of making metal castings, said improvement consisting in pouring "a mold in which a casting is to be formed, and sucking or drawing a heatabsorbing medium through the mold outside of the casting to carry off heat from said casting.

3. An improvement inthe artof making metal castings, said improvement consisting in pourin a mold -in which a casting is to be forme and, upon the format-ion of a crust on the body of hot metal in the mold and the creation of a space next exteriorly of said crust while the crusted body of metalor casting is' Within the mold, sucking or drawing a heat-absorbing medium through said space.

4. An improvement in the art of making metal'castings, said improvement consisting in chilling a body of molten metal supplied to a mold and thereby forming a chilled crust on said body, and then sucking or drawing a heat-absorbing medium to said chilled crust and through the mold.

5. An improvement in the art of making metal castings, said improvement consisting in forming a chilled crust on the body of hot metal supplied to the molten-receiving chamber of a mold and creating a-space next ex teriorly of said chilled crust while said body of metalis within the mold, and .then treating the crusted and already chilled body of hot metal or casting by suckin or drawing a heatabsorbing medium t rough said space.

6. An improvement in the art of making metal castings, said improvement consisting in pouring a mold having a circular chamber for receiving molten metal, and, upon the formation o a peripheral crust on the body of hot metal supplied to saidchamber and the creation of a space next exteriorly of and around said crust while said body of metal or castin is within the mold, sucking or drawing a eat-absorbing medium into and throu h said space all round the crusted body o? metal or casting.

47. An improvement in t e art of making circular metal castings, said improvement consisting in pouring a mold havinga cir- 'cular chamber for receiving molten metal and forming a chilled crust on and circumferentially of the bod of hot metal supplied to said chamber y chilling said bodyv exteriorly and circumferentially, and creating a splace next exteriorly of said chilled crust w ile the crusted and already chilled body of metal or casting is within the mold, and then sucking or drawing a heat-absorbing medium into and through said space.

8. An improvement in the art of making circular metal castings, said improvement consisting in pouring a mold having a circular chamber for receiving molten metal and forming a crust on and circumferentially of the body of hot metal supplied to said chamber, and creat-ing a space next exteriorly of said chilled crust While the crusted body of metal or casting is within the mold, and then Asucking or drawing a heat-absorbing medium into and endw'ise through said space all around the casting.

9. An improvement in the art of making inetal castings, said improvement consisting in pouring a mold having a circular chamber for receiving molten metal and forming a peripheral crust on the body' of hot metal supplied to said chamber and creating a space next exteriorly of and around said crust while said body of metal or casting is within the mold, and effecting the creation for said space of an `entrance and an exit which, extend all around andare spaced endwise of said space, and then causing a heatabsorbing medium to pass through said entrance, space and exit.

10. An improvement in the art of making metal castings, said improvement consisting in pouring a mold having a circular chamber for receiving molten metal and forming a peripheral crust on the body of hot metal supplied to said chamber and creating a space next exteriorly of and around said crust while said body of metal or casting is Within the mold, and during the creation of said space effecting the creation for said space of an entrance and an exit which extend ciroumferentially and are spaced en dwise of said space, and then sucking or drawing aheat-absorbing medium through said entrance, space and exit.

11. An improvement-in the art of making metal castings, said improvement consisting in pouring a mold having a circular chamber for receiving molten metal and formin a chilled peri heral curst on and circum erentially of t e body of hot metal supplied to said chamber and creating a space next exteriorly of and around said chilled crust while said body of metal or casting is within the mold, and effecting the creation for said space of an entrance and an exit which are spaced endwise of said chilled crust, and then causing a heat-absorbing medium to pass through said entrance, space and exit.

12. .An improvement in the art of casting a metal wheel havin a flange at one end of the tread of the w eel, said improvement consisting in pouring a mold having a circular chamber for receiving molten metal and, upon the formation of a peripheral crust on and circumferentially of the body of hot metal supplied to said chamber and While the crusted body of hot metal or casting is within the mold sucking or drawing a heat-absorbing medium transversely of the tread-forming surface of said peripheral crust Without drawin a heat-absorbing medium transversely o the peripheral surface of the flange of the casting'.

13. An improvement in the artV of casting a metal wheel having a flange at one Vend of the tread of the wheel, said improvement consisting in pouring a mold having a circular chamber for receiving molten metal and, upon the formation of a' peripheral crust on and circumerentially of the body of hot metal supplied to said chamber and the creation of a space next exteriorly of and around said crust while said body of metal or casting is within the mold, sucking or drawing a heat-absorbing medium through said space 'all around' the casting from the inner side of the flange transversely of said peripheral crust. l

14. An improvement in the art of casting a metal wheel having a flange at one end of the tread of the wheel, said vimprovement consisting in pouring a mold having a circular chamber for receiving molten met-al and effecting the formation of ,a chilled peripheral crust on the body of hot metal supplied to the mold by chilling said body exteriorly and circumferentially of the body, and then sucking or drawing a heat-absorbing medium to and transversely of the treadforming surface of thel casting.

15. An improvement in the art of casting a metal wheel having a flange at one end of the tread of the wheel, said improvement consisting in-pouring a mold having a circular chamber for receiving molten metal, and upon the formation of a peripheral orust on and circumferentially of the body of hot metal supplied to said chamber and the creation of a space next exteriorly of and around said crust while said body of metal or casting is within the mold, treating the throat-forming and the tread-forming por tion of the casting, without correspondingly treating the peripheral portion of the flange of the casting, by sucking or drawing a heatabsorbing medium into the aforesaid space in proximity to said throat-forming portion of the casting and thence endwise of and through said space at ithe tread-forming portion of the casting.

16. An improvement in the art of casting a metal wheel having a flange at one end'of the tread of the wheel, said improvement consisting in pouring a mold having a circular chamber for receiving molten metal and forming a chilled peripheral crust on and circumferentially of the body of hot metal supplied to said chamber and creat ing a space next exteriorly of and around said chilled crust while said body of metal or casting is within the mold, and then treating the throat-forming and the treadforming portion of the casting, Without correspondingly treating the peripherial portion of the flangelof the casting, by sucking or drawing a heat-absorbing medium into the aforesaid space in proximity to said throat-forming portion of the casting and thence endwise of and through said space at the tread-forming portion of the casting.

17. An improvement in the art of casting a metal car-wheel having a flange at one end of the tread of the wheel, said improvement consisting in pouring a mold having a circular chamber for receiving molten metal and forming a peripheral crust on and circumferentially of the body of hot f metal' supplied to said chamber and creating a space next exteriorly of and around said crust while the crusted'body of hotmet-al or casting is within the mold, and during the creation of said space effecting the creation for said space of an entrance and an exit which extend all around the casting at opposite endsrespectively ofthe treadforming portion ofthe casting, and then causing a heat-absorbing medium to pass through said entrance, space and exit.

18. An improvement in the art of casting a metal car-wheel having a flange at one end of the tread of the wheel, said improvement consisting in pouring a mold having a circular chamber for receiving molten metal and formin a chilled peripheral crust on and circum erentially of the body of hot metal supplied to said chamber and creat-- ing ya space next exteriorly of and around said chilled crust while the crusted body of hot metal or casting is within the mold, and

effectingthe creation for said space of an i entranceA and an exit which extend circumferentially of the casting adjacent opposite ends respectively of the tread-forming surface of the casting, and then sucking or drawing a heat-absorbing medium through said entrance, space and exit. f'

19. An improvement in the art of manufacturing a metal car-wheel havinga flanged end, said improvement consisting in casting the wheel flanged end lowermost and forming a chilled peripheral crust on and circumferentially of the casting, and creating a space next exteriorly of and around the casting while the casting is within the mold.y and effecting the creation for said space of an entrance and an exit which extend circumfegrentially of the casting adjacent the lower end and upper end'respectively of the tread-forming surface of the casting, and then causing a heat-absorbing medium to pass through said entrance, space and exit. 20. An improvement in the art of making an annular casting, said improvement consisting in pouring a mold having an annular circular chamber for receiving molten metal, and sucking or drawing a heat-absorbing medium through the mold centrally of the mold without contact of said heat-absorbing medium with the casting.

21. An improvement in the artV of making an annular metal casting, said improvement consisting in pouring a mold having an annular circular chamber for receiving molten metal, andfupon the formation of a peripheral crust on and eircumferentially of the body of hot metal supplied to said chamor drawing a heatabsorbing medium through the mold cent-rally of the iold.

22. An improvement inthe art of making an annular metal casting, said improvement consisting in' pouring a mold having an annular circular chamber for receiving molten metal, and, uponthe| formation of a peripheral crust on and circumferentially of the body of hot metal su plied to said chamber causing a heat-absor lng medium .to pass into contact with and transversely of said crust, and simultaneously causing aheatabsorbing medium to pass through the mold centrally of the mold.

In testimony whereof, I sign the foregomg speclcatlon, in the presencq of two witnesses.

l THOMAS D. WEST.

Witnesses:

B. C. BROWN, N. L. MCDONNELL. 

